DNA is one of the most thoroughly characterized molecules with regard to structure, chemistry, and modification, and has the capability to serve a wide variety of functions. It can be, and has been, used as a scaffold for the integration of varying entities due to its well defined ability to base-pair hybridize. With the discovery of aptamers and the realization that DNA has the capability to structurally and chemically recognize other molecules with near anti-body specificity at a fraction of the difficultly of synthesis, a new field of DNA based targeting molecules was born. Today there are FDA approved therapeutics based solely on DNA, such as the VEGF aptamer.
Current nanoparticle-based approaches to treating cancer include constructs composed of polymer, silica, or gold nanoparticles, liposomes, and less frequently such platforms as carbon nanotubes and viral capsids. These structures are coated with a variety of functionalizing entities such as polyethylene glycol (PEG) for biocompatibility, various targeting peptides, antibodies, small molecules, or aptamers and some form of therapeutic.